This invention relates to a well drilling equipment, and more particularly to an apparatus designed to facilitate recovery of downhole equipment stuck in a downhole formation and/or cased hole.
During drilling operations, there is an ever present danger of a drill pipe being stuck in the well bore without the possibility of recovering the drill string with the help of conventional equipment. Some of the conventional methods of recovery of such equipment utilize reciprocating movement of a work string, moving the pipe up and down in an effort to recover the stuck equipment. Another method utilizes rotational movement by importing torque to the pipe in a clockwise or counter-clockwise direction. A third method employs circulating fluids around the downhole equipment to facilitate recovery of that equipment.
While the above described conventional methods work satisfactory under many conditions, there are still a number of areas wherein utilization of any of the above methods alone results in a limited success. For example, a drill string can get stuck in a dehydrated mud in a cased hole, or the tubing becomes stuck in the sand or other dense formation. In such cases, the recovery of the equipment becomes a long, labor-consuming process which adversely affects the efficiency of the drilling operation and is costly.
The present invention contemplates provision of a system for recovery of equipment which can be used in conjunction with conventional methods or alone.